Methods and apparatus for recovering heat from processing systems

ABSTRACT

Methods and apparatus for recovering heat from disposed effluents are disclosed herein. In some embodiments, an apparatus may include a first process chamber configured for gaseous or liquid processes; a second process chamber configured for liquid processes; and a heat pump having a compressor and a first heat exchanger, wherein the compressor is configured to use a first effluent exhausted from the first process chamber and wherein the first heat exchanger having first and second sides configured to transfer heat therebetween, wherein the first side is configured to flow a liquid reagent therethrough and into the second process chamber, and wherein the second side is configured to flow the pressurized first effluent from the first process chamber therethrough. In some embodiments, a heater may be disposed between the heat pump and the second process chamber to further heat the liquid reagent prior to entering the second process chamber.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of U.S. provisional application Ser. No.61/105,949, filed Oct. 16, 2008, and U.S. provisional application Ser.No. 61/229,812, filed Jul. 30, 2009, each of which are hereinincorporated by reference.

BACKGROUND

1. Field

Embodiments of the present invention generally relate to semiconductor,flat panel, photovoltaic or other silicon and thin film processingchambers and equipment, and more specifically to methods and apparatusfor recovering heat from such processing systems.

2. Description of the Related Art

In semiconductor, flat panel, photovoltaic, and other silicon or thinfilm processing systems, many processes require the pre-heating ofliquid or gaseous reagents prior to use in the processing system. Thereagents are often heated using a heater, such as a point of use heater,or a similar heating apparatus, immediately prior to use. Afterprocessing, effluents (e.g., used, or “dirty” water or chemicals,gaseous exhaust, and the like) disposed from the processing system istypically directed to a waste treatment system to treat and/or disposeof the effluent. Very often these effluents need to be cooled downbefore they can be disposed or diluted with a cooler medium or dissipateheat into the ambient air, which in turn often needs to be removed aswell.

As pre-heating of the reagents requires a significant amount of energy,which can increase manufacturing costs, the present invention isdirected towards methods and apparatus for recovering heat from disposedeffluents to facilitate reduction in such manufacturing costs.

SUMMARY

Methods and apparatus for recovering heat from disposed effluents aredisclosed herein. In some embodiments, an apparatus includes a substrateprocessing system comprising a process chamber configured for liquidprocesses; a first heat exchanger having first and second sidesconfigured to transfer heat therebetween, wherein the first side isconfigured to flow a liquid reagent therethrough and into the processchamber, and wherein the second side is configured to flow an effluentfrom the process chamber therethrough; and a heater disposed in linewith the first side of the first heat exchanger to heat the liquidreagent prior to entering the process chamber.

In some embodiments, a substrate processing system may include a wasteheat source for providing a first waste fluid having waste heat storedtherein; a first process chamber having a reagent source coupled theretoand configured to provide a reagent to an inner volume of the firstprocess chamber; and a heat pump coupled between the waste heat sourceand an incoming reagent line that flows the reagent into the innervolume of the process chamber, the heat pump configured to transfer heatfrom the waste heat source to the reagent in the incoming reagent line.In some embodiments, the heat pump may include a compressor and a firstheat exchanger, wherein the compressor is coupled in line with the wasteheat source and a first side of the heat exchanger to pressurize thefirst waste fluid and prior to the first waste fluid flowing through thefirst side of the heat exchanger, and wherein a second side of the firstheat exchanger is configured to flow the reagent therethrough.

In some embodiments, the system further includes a heater disposed inline with the second side of the first heat exchanger to heat thereagent prior to entering the first process chamber. In someembodiments, the waste heat source may comprise one or more of aneffluent from a process chamber configured for liquid or gaseousprocesses, a compressed air system, an air separation compressor, agaseous exhaust or a liquid coolant from an abatement device, hot air ora liquid coolant from electrical and/or mechanical equipment, or thelike.

In some embodiments, the first process chamber is configured for liquidprocesses, and wherein the waste heat source comprises a second processchamber configured for gaseous processes and providing the first wasteheat as gaseous exhaust from the second process chamber.

In some embodiments, the system further includes a second heat exchangerhaving first and second sides configured to transfer heat therebetween,wherein the first side of the second heat exchanger is configured toflow the reagent therethrough and into the first process chamber, andwherein the second side of the second heat exchanger is configured toflow a second waste fluid exhausted from the first process chambertherethrough.

In one aspect of the invention, methods for recovering heat fromdisposed effluents are disclosed. In some embodiments, a method forprocessing a substrate includes providing a process chamber configuredfor liquid processes coupled to a heat exchanger having a first side forflowing a liquid reagent into the processing system and a second sidefor flowing an effluent from the process chamber—directly or pumped froman intermediate reservoir; pre-heating the liquid reagent bytransferring heat from the effluent flowing through the second side ofthe heat exchanger to the reagent flowing through the first side of theheat exchanger; and heating the pre-heated liquid reagent to a desiredtemperature using a heater disposed between the heat exchanger and theprocess chamber.

In some embodiments, a method for processing a substrate includesflowing a liquid reagent through a first side of a heat exchanger topreheat the liquid reagent; heating the pre-heated liquid reagent to adesired temperature using a heater; flowing the heated liquid reagent toa process chamber configured for liquid processes; and flowing a processeffluent from the chamber (directly or pumped from an intermediatereservoir) through a second side of the heat exchanger to pre-heat theliquid reagent flowing through the first side of the heat exchanger.

In some embodiments, a method for processing a substrate may includeflowing a reagent through a heat pump coupled to a waste heat source toheat the reagent by transferring heat from the waste heat source to thereagent; and flowing the heated reagent to a process chamber to processthe substrate. In some embodiments, a method for processing a substratemay include flowing a reagent through a first side of a first heatexchanger to heat the reagent by transferring heat from a pressurizedwaste heat fluid flowing through a second side of the first heatexchanger; and flowing the heated reagent to a process chamber toprocess the substrate. In some embodiments, the waste heat source or thewaste heat fluid may comprise one or more of a liquid waste fluid,exhaust or liquid coolant from a process chamber configured for gaseousprocesses, a compressed air system, an air separation compressor agaseous exhaust or an liquid coolant from an abatement device, hot airor a liquid coolant from electrical and/or mechanical equipment, or thelike.

Other and further embodiments are described in the detailed description,below.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention can be understood in detail, a more particular description ofthe invention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 illustrates a schematic processing system in accordance with someembodiments of the present invention.

FIG. 2 illustrates a semiconductor processing system in accordance withsome embodiments of the present invention.

FIGS. 3-3A illustrate a semiconductor processing system in accordancewith some embodiments of the present invention.

FIG. 4 illustrates a semiconductor processing system in accordance withsome embodiments of the present invention.

FIG. 5 illustrates a semiconductor processing system in accordance withsome embodiments of the present invention.

FIG. 5A illustrates a heat recovery apparatus in accordance with someembodiments of the present invention.

FIG. 6 illustrates a flow chart of a method for recovering heat from adisposed effluent in accordance with some embodiments of the presentinvention.

FIG. 7 illustrates a flow chart of a method for recovering heat from adisposed effluent in accordance with some embodiments of the presentinvention.

FIG. 8 illustrates a flow chart of a method for recovering heat from adisposed effluent in accordance with some embodiments of the presentinvention.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. The above drawings are not to scale and may be simplifiedfor illustrative purposes.

DETAILED DESCRIPTION

Methods and apparatus for recovering and utilizing heat from disposedeffluents in processing systems are disclosed herein. The inventivemethods and apparatus advantageously facilitate reduced energyconsumption in substrate processing systems (for example, semiconductor,flat panel, photovoltaic or other silicon and thin film processingsystems) by utilizing waste heat from the processing system (forexample, disposed effluent from a process chamber as well as waste heatgenerated by other components of the processing system) to pre-heatfluids prior to use in the same and/or other processing systems. Thereduction of heat in the disposed effluent is further advantageous forsubsequent processing of the disposed effluents, such as by abatement orother means of disposal.

FIG. 1 illustrates a schematic processing system in accordance with someembodiments of the present invention. A processing system 1 may operatea process that requires a heated input (gaseous or liquid). In theexample of FIG. 1, an input 2, such as cold ultrapure water (UPW), isbeing provided to a process chamber 3. The processing system furtherincludes a plurality of waste heat sources 4, 5, 6. The waste heatsources may be processing equipment, abatement equipment, air handlingequipment, or the like, as discussed in more detail below. In someembodiments, a waste heat source (e.g., waste heat source 4) can bedisposed effluents from the process chamber 3 itself as illustrated bythe dotted line connecting the process chamber 3 and waste heat source4. The processing system 1 includes one or more heat pumps 7 to transferheat from the waste heat sources 5, 6 to heat the input to the processchamber 3 prior to disposal in an effluent system 10. If compatible, thewaste heat sources 5, 6 may be aggregated and run through the same heatpump (as shown). Alternatively, waste heat that is incompatible may berun through a separate heat pump system (not shown). Optionally, apre-heater (such as a heat exchanger 8) may be used to transfer heatfrom exhaust/effluent not compatible with the heat pump 7 to the input 2to the process chamber 3 prior to disposal in an effluent system 11. Insome embodiments, effluent systems 10 and 11 are the same effluentsystem. Also optionally, a heater 9 may be provided to further heat theinput 2, if necessary, to the desired temperature for a process. Themany variants of this system are discussed below.

FIG. 2 illustrates a substrate processing system 100 in accordance withsome embodiments of the present invention. The semiconductor processingsystem 100 may include a process chamber 102 configured for performingwet process (e.g., wet bench processes). The process chamber 102 may beany suitable processing chamber configured for liquid processes havingincoming liquid reagents in need of heating and disposed effluents fromwhich heat may be recovered. Suitable processing chambers may includeany single substrate or batch cleaning system, such as a chamberconfigured for wet chemical etch or clean, such as pre-thermal orpost-strip wet cleans, or the like. Exemplary processing chambers mayinclude the OASIS STRIP™ or OASIS CLEAN™ chambers, available fromApplied Materials, Inc. of Santa Clara, Calif.

As shown in FIG. 1, the process chamber 102 may include a substratesupport 112 for holding a substrate 114. The substrate 114 may be anysuitable material to be processed, such as a crystalline silicon (e.g.,Si<100> or Si<111>), a silicon oxide, a strained silicon, a silicongermanium, a doped or undoped polysilicon, a doped or undoped siliconwafers, patterned or non-patterned wafers, silicon on insulator (SOI),carbon doped silicon oxides, silicon nitride, doped silicon, germanium,gallium arsenide, glass, sapphire, a display substrate (such as a liquidcrystal display (LCD), a plasma display, an electro luminescence (EL)lamp display, or the like), a solar cell array substrate, a lightemitting diode (LED) substrate, or the like. The substrate 114 may havevarious dimensions, such as 200 mm or 300 mm diameter wafers, as well asrectangular or square panels. The frontside surface of the substrate 114may be hydrophilic, hydrophobic, or a combination thereof. The frontsidesurface may be patterned, or having one or more patterned layers, suchas a photomask, disposed thereon.

The substrate 114 may be disposed in a recess 116 formed on the surfaceof the substrate support 112. The recess 116 may be utilized, forexample, to immerse the substrate 114 in bath of reagents. The reagentsmay be supplied by a nozzle 118 disposed above the support 112. Therecess 116 need not be limited to a depression formed in the surface ofthe substrate support. As such, the recess 116 may be formed, forexample, by an edge ring or bracket (not shown) configured to supportthe substrate 114 at a peripheral of the substrate, where the substrate114 forms the base of the recess. The substrate support may furtherinclude a plate (not shown) disposed about 3 millimeters (mm) below thebackside of the substrate 114. The plate may include transducers (notshown) that are capable of emitting sound in the megasonic frequencyrange, or between about 800 to about 2000 kHz.

A fluid feed port (not shown) can be disposed in the substrate support112 and through the plate to supply fluid to fill an about 3 mm gap (notshown) between the plate and the backside of the substrate 112 with aliquid during processing. The liquid can act as a carrier fortransferring megasonic energy to the substrate 114, for example, as ameans of providing agitation during a cleaning process, or as a way toheat the wafer. The substrate support 112 may further include alift/rotation mechanism (not shown) which may, for example, be utilizedto controllably spread a reagent uniformly across the frontside surfaceof the substrate 114. The top of the process chamber 102 can include afilter (not shown) to clean air that is flowing into the processingchamber and onto the frontside of the substrate 114.

The nozzle 118 may be coupled to an incoming fluid line 104 at a wall ofthe process chamber 102. The nozzle can be positioned to direct flow ofa gas, vapor, or a liquid onto the frontside surface of the substrate114. In some embodiments, the nozzle 118 may dispense a reagent to fillthe recess 116, thus immersing the frontside surface of the substrate114 in the reagent. In some embodiments, the nozzle may dispense areagent to be spread uniformly across the frontside surface of thesubstrate 112. For example, the frontside surface may be covered with areagent by dispensing the reagent from the nozzle at a flow ratesufficient to cover the frontside surface of the substrate 114 with thereagent while maintaining a rotation rate sufficient to cover thefrontside surface with the reagent.

A reagent source 108 is coupled to the process chamber 102 via theincoming fluid line 104 to provide a liquid reagent to the processchamber 102, for example, via the nozzle 118. A heater 120 may bedisposed along the fluid line 104 for heating a liquid reagent flowingtherethrough prior to use in the process chamber 102. The heater 120 maybe disposed at any suitable point along the fluid line 104, for example,as close as possible to the process chamber 102 to minimize heat loss.The heater 120 may be, for example, a point of use heater, or othersuitable heating apparatus for heating a reagent to a desiredtemperature. For example, in some embodiments, the liquid reagentsupplied by the reagent source 108 may be at a temperature of betweenabout 15 to about 180 degrees Celsius. In some embodiments, the heater120 may heat the liquid reagent to a temperature of between about 35 toabout 180 degrees Celsius.

A heat exchanger 103 is disposed in-line with the incoming fluid line104, upstream of the heater 120, to preheat the liquid reagent comingfrom the reagent source 108 prior to flowing past the heater 120. Theheat exchanger 103 generally includes a first side and a second sidethat are robustly thermally coupled for transferring heat therebetween.The first side of the heat exchanger 103 is coupled in-line with theincoming fluid line 104 such that the liquid reagent supplied by thereagent source 108 flows therethrough. The second side of the heatexchanger 103 is coupled in-line with an effluent line 106 of theprocess chamber 102 for flowing effluent from the process chamber 102therethrough.

Heat stored in the effluent coming from the process chamber 102 istransferred to the liquid reagent being provided to the process chamber102 via the heat exchanger 103. For example, in some embodiments, theeffluent discharged from the process chamber 102 after processing may beat a temperature of between about 30 to about 180 degrees Celsius. Theheat stored in the effluent may thus be used to pre-heat the liquidreagent provided to the process chamber 102, thereby reducing the powerrequired by the heater 120 to heat the liquid reagent. In someembodiments, pre-heating the liquid reagent using heat transferred fromthe effluent line 106 may reduce energy consumption by the heater 120 byat least about 20 percent.

The heat exchanger 103 may be any suitable heat exchanger for exchangingheat between two liquids and may be of any suitable size, dependent uponthe physical space available. In some embodiments, the heat exchanger103 may be a non-pressurized system where the effluent may flow throughthe second side of the heat exchanger under force of gravity. In someembodiments, the heat exchanger 103 may be a pressurized system wherethe effluent may, for example, collect in a tank, or intermediatereservoir 105, and may be pumped through the second side of the heatexchanger.

Although shown as separate components, in some embodiments, the heatexchanger 103 may be integrated with the heater 120 in a single devicethat provides both functions as described above. In some embodiments,the heat exchanger 103 may be integrated with the process chamber 102,such that a liquid reagent need only be heated to lesser temperaturesprior to delivery to the process chamber through the heat exchanger,which may raise the temperature of the liquid reagent to the desiredprocessing temperature, or which may have an outlet configured to allowattachment of a heater thereto.

The effluent line 106 may be coupled to the base of the process chamber102. The base of the process chamber 102 need not be horizontal asillustrated in FIG. 1, and may generally be sloped such that disposedeffluents flow towards a singular location, such as a drain disposed inthe base and having the effluent line 106 coupled thereto. The effluentfrom the process chamber 102 flows through the effluent line 106 to, forexample, an effluent system 110 for treatment and/or disposal of theeffluent. The effluent system 110 may include, for example, an abatementsystem or other system suitable for disposal of the effluent.

The incoming fluid line 104 may comprise any suitable materials thatfacilitate robust heat transfer between the effluent line 106 and aliquid reagent in the fluid line. The effluent line 106 may comprise anysuitable materials that facilitate robust heat transfer between theeffluent and the fluid line 104. In some embodiments, the materials mayhave a high thermal conductivity (e.g., greater than or equal to about300 W/mK). In some embodiments, the thermal conductivity may be lower,e.g., when polymers need to be used due to material compatibility. Insome embodiments, the materials may include at least one of copper,steel, stainless steel, galvanized steel, titanium, tungsten, highnickel content alloys, carbon, polymer, silicon, silicon coated metal,aluminum, carbon, quartz, ceramics, and glass, as well as ceramic and/orglass coated materials. In some embodiments, the material of theincoming fluid line 104 may further be selected based on chemicalcompatibility with a reagent. In some embodiments, the material of theeffluent line 106 may further be selected based on chemicalcompatibility with the disposed effluents.

As discussed above, a portion of the effluent line 106 (i.e., the secondside of heat exchanger 103) is thermally coupled to a portion of theincoming fluid line 104 (i.e., the first side of heat exchanger 103).Alternatively, the effluent line 106 may be coiled about the fluid line104, or thermally coupled to the incoming fluid line 104 in any suitableconfiguration so as to maximize heat transfer between an effluentflowing in the effluent line 106 and a liquid reagent flowing in theincoming fluid line 104 to the process chamber 102 (e.g., essentiallyforming a heat exchanger by configuration of the effluent line 106 andthe incoming fluid line 104). Alternatively or in combination, a portionof the effluent line 106 may be thermally coupled to the reagent source108 to facilitate heat transfer to a reagent in the fluid line 104.

The processing system 100 further includes a controller 122 coupled tothe process chamber 102 to control the operation thereof and/or tocontrol one or more other components of the processing system 100. Thecontroller 122 generally comprises a central processing unit (CPU), amemory, and support circuits (not shown). The controller 122 controlsthe process chamber 102 and various chamber components directly or,alternatively, via individual controllers (not shown) associated witheach chamber component. In some embodiments, other control elements canbe used, such as, for example, industrial controllers without a CPU.

In operation, and initially, a liquid reagent may flow into the incomingfluid line 104 from the reagent source 108 and heated to a desiredtemperature by the heater 120. The reagent may then flow into theprocess chamber 102 and through the nozzle 118 to the substrate 114. Thereagent reacts and/or becomes contaminated with materials from, ordisposed on, the substrate 114 thereby becoming an effluent. Theeffluent is disposed at the base of the chamber 102 via the effluentline 106. The effluent line 106 transfers heat from the effluent to aliquid reagent in the fluid line 104 via the heat exchanger 103. Theliquid reagent, having an elevated temperature from the heat recoveredfrom the effluent, requires less energy from the heater 120 prior toentering the process chamber 102. Thus, the recovered heat from theeffluent may reduce energy consumption by the processing system 100, andin some embodiments, the heater 120.

Alternatively, waste heat may be provided by an external waste heatsource instead of internally recycling waste heat from disposedeffluents as discussed above. An exemplary processing system whichrelies on an external waste heat source is described below andillustrated in FIG. 3.

FIG. 3 illustrates a substrate processing system in accordance with someembodiments of the present invention. The semiconductor processingsystem includes a semiconductor processing system 300 and a waste heatrecapture system 301 configured to pre-heat a reagent for use in thesystem 300. The semiconductor processing system 300 is substantiallysimilar to the processing system 100. However, an effluent line 107coupling the intermediate reservoir 105 to the effluent system 110 doesnot provide waste heat to the incoming fluid line 104 in the system 300as the effluent line 106 does for the system 100.

The waste heat recapture system 301 includes a heat pump 124 coupled toa waste heat source 123 via a waste heat conduit 125 and to the incomingfluid line 104 of the system 300 (or other fluid line that is desired tobe heated). The waste heat recapture system 301 uses the waste heat fromthe waste heat source 123 to pre-heat a reagent flowing through theincoming fluid line 104.

The waste heat source 123 may be any suitable source of waste heat fromliquid or gaseous processes or other fab equipment, for example, such asa liquid chemical from a heated bath, a liquid coolant or a gaseousexhaust from a process chamber configured for gaseous processes, processpump stacks, other chamber equipment (such as plasma sources, heaters,hot water exhaust, or the like), a compressed air system, an airseparation compressor, air compressors, a gaseous exhaust or a liquidcoolant from an abatement device, hot air or a liquid coolant fromelectrical and/or mechanical equipment, and the like. The heat pump 124is disposed in-line with a waste heat conduit 125. The waste heatconduit 125 may further couple the waste heat source 123 to an exhaustsystem 129. The exhaust system 129 may be, for example, an abatementsystem, or another suitable waste processing system. The waste heatconduit 125 may be typically utilized for transported gaseous effluentsexhausted from the waste heat source 123 to the exhaust system 129.

In some embodiments, the heat pump 124 includes a compressor 126 and aheat pump heat exchanger 128. Although shown as separate components, insome embodiments, the heat pump 124 further include (e.g., may beintegrated with) the heater 120 or with a different heater. The heatpump may operate similar to a liquid to water geothermic heat pump.Alternatively, the heat pump 124 may be adapted for optionally couplingto a heater, such as the heater 120, should a heater be required.

In some embodiments, the compressor 126 may be disposed in-line with thewaste heat conduit 125 between the waste heat source 123 and the heatpump heat exchanger 128. The compressor 126 may be any suitable devicefor compressing a gaseous effluent. The increased pressure of thegaseous effluent facilitates improved heat transfer in the heat pumpheat exchanger 128 by increasing the temperature of the effluent in thewaste heat conduit 125.

The heat pump heat exchanger 128 may be any suitable heat exchanger forexchanging heat between the waste effluent and an incoming fluid and maybe of any suitable size, dependent upon the physical space available.The heat pump heat exchanger 128 is disposed in-line with the incomingfluid line 104, upstream of the heater 120 (if present), to preheat thereagent coming from the reagent source 108 prior to entering the processchamber 102 (or other location where the heated reagent is to be used).The heat pump heat exchanger 128 generally includes a first side and asecond side that are robustly thermally coupled for transferring heattherebetween. The first side of the heat pump heat exchanger 128 iscoupled in-line with the incoming fluid line 104 such that the reagentsupplied by the reagent source 108 flows therethrough. The second sideof the heat pump heat exchanger 128 is coupled in-line with the wasteheat conduit 125 for flowing effluent from the waste heat source 123therethrough.

In operation, the reagent flowing through the incoming fluid line 104may be heated within the heat pump heat exchanger 128 via thermaltransfer of heat from the waste effluent flowing through the waste heatconduit 125. The compression of the waste effluent by the compressor 126prior to flowing through the heat pump heat exchanger 128 enhancesthermal transfer by increasing the temperature of the waste effluent.

Heat stored in the waste effluent coming from the waste heat source 123is transferred to the reagent being provided to the process chamber 102via the heat pump heat exchanger 128. For example, in some embodiments,the gaseous effluent discharged from the waste heat source 123 may be ata temperature of between about 30 to about 90 degrees Celsius. The heatstored in the gaseous effluent may thus be used to pre-heat the reagentprovided to the process chamber 102, thereby reducing, or eliminatingthe need for power required by the heater 120 to heat the liquid reagentto the desired temperature. In some embodiments, pre-heating the reagentusing heat transferred from the waste heat conduit 125 may reduce energyconsumption by the heater 120. In some embodiments, the heat transferredfrom the waste heat conduit 125 may completely remove the need forfurther heating by the heater 120.

At least within the heat pump heat exchanger 128, the incoming fluidline 104 and the waste heat conduit 125 may comprise anyprocess-compatible, suitable materials that facilitate robust heattransfer between the waste heat conduit 125 and the fluid in the fluidline. In some embodiments, the materials may have a high thermalconductivity (e.g., greater than or equal to about 300 W/mK). In someembodiments, the thermal conductivity may be lower, e.g., when polymersneed to be used due to material compatibility. In some embodiments, thematerials may include at least one of copper, steel, stainless steel,galvanized steel, titanium, tungsten, high nickel content alloys,carbon, polymer (such as non-limiting examples of polymethylpentene(PMP, such as TPX®), polyphenylsulfide (PPS), polytetrafluorethylene(PTFE) and other fluorinated or cross linked fluorinated polymers),silicon, silicon coated metal, aluminum, carbon (including crystalline,amorphous, and vitreous graphite), quartz, ceramics, glass, composites,as well as ceramic and/or glass coated materials. In some embodiments,the material of the incoming fluid line 104 and/or the waste heatconduit 125 may further be selected based on chemical compatibility withthe respective fluids flowing therein.

As discussed above, a portion of the waste heat conduit 125 (e.g., thesecond side of heat pump heat exchanger 128) is thermally coupled to aportion of the incoming fluid line 104 (e.g., the first side of heatpump heat exchanger 128). The waste heat conduit 125 may be coiled aboutthe fluid line 104, or may be thermally coupled to the incoming fluidline 104 in any suitable configuration so as to enhance, or maximize,heat transfer between an effluent flowing in the waste heat conduit 125and a reagent flowing in the incoming fluid line 104 to the processchamber 102. Alternatively or in combination, a portion of the wasteheat conduit 125 may be thermally coupled to the reagent source 108 tofacilitate heat transfer to a reagent in the fluid line 104.

In some embodiments, and as depicted in FIG. 3A, the heat pump 124 mayutilize a closed loop system having a heat transfer fluid disposedwithin an inner conduit of the heat pump 124. One portion of the innerconduit forms part of a first heat pump heat exchanger 128 _(A) with thewaste heat conduit 125. Another portion of the inner conduit forms partof a second heat pump heat exchanger 128 _(B) with the incoming fluidline 104. In operation, the heat pump 124 transfers heat from the wasteheat source to the heat transfer fluid via the first heat pump heatexchanger 128 _(A), which vaporizes the heat transfer fluid. Thevaporized heat transfer fluid is then compressed by the compressor 126and pumped to the second heat pump heat exchanger 128 _(B) to transferthe heat from the heat transfer fluid to the fluid flowing in theincoming fluid line 104. The configuration of the heat pump in FIG. 3Amay be utilized in any of the embodiments of heat pumps describedherein.

Returning to the process chamber 102, the effluent line 107 may becoupled to the base of the process chamber 102. The base of the processchamber 102 need not be horizontal as illustrated in FIG. 1, and maygenerally be sloped such that disposed effluents flow towards a singularlocation, such as a drain disposed in the base and having the effluentline 107 coupled thereto. The effluent from the process chamber 102flows through the effluent line 107 to, for example, the effluent system110 for treatment and/or disposal of the effluent. In some embodiments,the disposed effluents may, for example, collect in a tank, orintermediate reservoir 105, which is disposed in the effluent line 107.In some embodiments, the disposed effluents may be pumped from thereservoir 105 and through a heat exchanger (heat pump heat exchanger128, or a different heat exchanger) to further pre-heat a reagent in theincoming fluid line 104 as shown in FIG. 4, discussed below.

The processing system 300 further includes the controller 122 coupled tothe process chamber 102 to control the operation thereof and/or tocontrol one or more other components of the processing system 300 and/orthe waste recapture system 301. The controller 122 generally comprises acentral processing unit (CPU), a memory, and support circuits (notshown). The controller 122 controls the process chamber 102 and variouschamber components directly or, alternatively, via individualcontrollers (not shown) associated with each chamber component. In someembodiments, other control elements can be used, such as, for example,industrial controllers without a CPU.

In operation, a reagent may flow into the incoming fluid line 104 fromthe reagent source 108 and heated to a desired temperature by the heatpump 124. Effluent exhausted from the waste heat source 123 ispressurized by the compressor 126, thus raising the temperature of theeffluent. The pressurized effluent flows through the second side of theheat pump heat exchanger 128 and transfers heat to the reagent disposedin the incoming fluid line 104. The pre-heated reagent may then flowinto the process chamber 102 and through the nozzle 118 to the substrate114. The reagent reacts with and/or becomes contaminated by materialsfrom, or disposed on, the substrate 114, thereby becoming an effluent.The effluent is disposed at the base of the chamber 102 via the effluentline 106 to the exhaust system 110. Optionally, should the reagentrequire additional heating, the heater 120 may be utilized to furtherpre-heat the reagent prior to entering the process chamber 102.

Alternative embodiments of the processing system depicted in FIG. 3 arepossible. For example, the system 300 is exemplary, and may beconfigured for processes other than liquid processes, for examplegaseous processes wherein the reagent may be a gaseous reagent. Further,the configuration of the waste heat recapture system 301 is exemplary,and may be configured in other suitable arrangements. For example, thewaste heat recapture system 301 need not be configured for the disposalof gaseous effluents. For example, the waste heat recapture system 301may be a closed loop system for removing heat, such as a refrigerationunit, or other such closed loop system utilizing a heat pump. Forexample, the heat disposal side of such as closed loop system may becoupled to the incoming fluid line 104.

Further, the embodiments discussed above for the systems 100 and 300 canbe combined into one processing system. Exemplary system combinationsare discussed below and illustrated in FIGS. 4-5.

For example, FIG. 4 illustrates a semiconductor processing system inaccordance with some embodiments of the present invention. For example,a semiconductor processing system 400 may includes the processing system100 and a processing system 450. The semiconductor processing system 400may be an exemplary portion of a fabrication line, and further such afabrication line may comprise a plurality of interconnected processsystems, and need not be limited to two systems as illustrated. Asillustrated in FIG. 4, the second processing system 450 may be coupledto the processing system 100 at the incoming fluid line 104 tofacilitate pre-heating of a reagent prior to entering the processchamber 102. Similar to the concepts discussed above, the processingsystem 400 may facilitate the recovery of waste heat from both theprocessing systems 100 and 450.

The process system 100 is substantially described above. As depicted inFIG. 4, the process system 100 includes a heat exchanger 103 disposedin-line with the incoming fluid line 104, upstream of the heater 120, topreheat the reagent coming from the reagent source 108 prior to flowingpast the heater 120.

The semiconductor processing system 450 illustrates one specific exampleof a secondary system being utilized as part of the waste heat recapturesystem 301 discussed above. The semiconductor processing system 450includes a process chamber 452 which may be configured for gaseousprocessing. The process chamber 452 may include exemplary gaseousprocessing chambers as discussed above. Further, the process chamber 452may include any suitable system utilizing gaseous processes, such ascompressed air systems, abatement devices, air separation compressors,and the like.

The processing system 450 includes a heat pump 454 disposed in-line withthe incoming fluid line 104, upstream of the heater 120 (when present),to preheat the reagent coming from the reagent source 108 prior toflowing into the process chamber 102. The heat pump 454 generallyincludes a compressor 456 and a heat pump heat exchanger 458. Thecompressor 456 may be disposed in-line with an exhaust line 160 of theprocess chamber 452. The compressor 456 may be any suitable compressorfor pressurizing a gaseous effluent, such as the compressor 126discussed above.

The heat exchanger 454 is disposed downstream of the compressor 456, forexample, such that a gaseous effluent exhausted from the chamber 152would enter the compressor 456 prior to entering the heat exchanger 454.The heat exchanger 454 may be substantially similar to the heat pumpheat exchanger 128, with the noted exception that the heat exchanger 454comprises components of both system 100 (a portion of the incoming fluidline 104) and system 450 (a portion of the exhaust line 160). The heatpump heat exchanger 458 includes a first side and a second side that arerobustly thermally coupled for transferring heat therebetween. The firstside of the heat pump heat exchanger 458 is coupled in-line with theincoming fluid line 104 such that the reagent supplied by the reagentsource 108 flows therethrough. The second side of the heat pump heatexchanger 458 is coupled in-line with the effluent line 460 of theprocess chamber 452 for flowing pressurized gaseous effluent from theprocess chamber 452 therethrough.

Heat stored in the gaseous effluent or the liquid coolant coming fromthe process chamber 452 is transferred to the reagent being provided tothe process chamber 102 via the heat pump 454. For example, in someembodiments, the gaseous effluent or liquid coolant discharged from theprocess chamber 452 after processing may be at a temperature of betweenabout 30 to about 300 degrees Celsius. The temperature of the exhaustedgaseous effluent or liquid coolant may be increased via pressurizationby the compressor 456. The heat stored in the pressurized gaseouseffluent may thus be used to pre-heat the reagent provided to theprocess chamber 102, thereby reducing the power required by the heater120 to heat the liquid reagent. In some embodiments, pre-heating theliquid reagent using heat transferred from the gaseous effluent line 460reduces energy consumption by the heater 120. When combined with heatrecovered via the heat exchanger 103, the combined heat transferred fromthe gaseous effluent line 460 and effluent line 106 further reducesenergy consumption by the heater 120, and may eliminate the need for theheater 120.

The effluent line 460 may be coupled to the base of the process chamber102. The effluent exhausted from the process chamber 452 flows throughthe effluent line 160 to, for example, an effluent system 462 fortreatment and/or disposal of the effluent. The effluent system 462 mayinclude, for example, an abatement system or other system suitable fordisposal of the effluent.

The effluent line 460 may comprise any suitable materials thatfacilitate robust heat transfer between the gaseous effluent and thefluid line 104. In some embodiments, the materials may have a highthermal conductivity (e.g., greater than or equal to about 300 W/mK). Inother embodiments the thermal conductivity may be lower, e.g. whenpolymers need to be used due to material compatibility. In someembodiments, the materials include those materials utilized with exhaustline 106. In some embodiments, the material of the effluent line 460 mayfurther be selected based on chemical compatibility with a gaseousprocess, for example, such as an etch process or other such processwhich may produce corrosive effluents.

As discussed above, a portion of the effluent line 460 (e.g., the secondside of heat exchanger 158) is thermally coupled to a portion of theincoming fluid line 104 (e.g., the first side of heat pump heatexchanger 458). For example, the effluent line 460 may be coiled aboutthe fluid line 104, or thermally coupled to the incoming fluid line 104in any suitable configuration so as to maximize heat transfer between aneffluent flowing in the effluent line 460 and a reagent flowing in theincoming fluid line 104 to the process chamber 102. Alternatively or incombination, a portion of the effluent line 460 may be thermally coupledto the reagent source 108 to facilitate heat transfer to a reagent inthe fluid line 104.

The processing system 450 further includes a controller 464 coupled tothe process chamber 452 to control the operation thereof and/or tocontrol one or more other components of the processing system 450. Thecontroller 464 is substantially equivalent to the controller 122, andcontrols the process chamber 102 and various chamber components directlyor, alternatively, via individual controllers (not shown) associatedwith each chamber component. Further, the processing system 400 mayfurther include a central controller (not shown) for controlling thecomponents of each processing system (e.g., processing systems 100, 450)directly or, alternatively via individual controllers, such ascontrollers 122, 464 associated with each system.

In operation, a reagent may flow into the incoming fluid line 104 fromthe reagent source 108. In some embodiments, the reagent may beinitially heated to a desired temperature by the heater 120. The reagentmay then flow into the process chamber 102 and through the nozzle 118 tothe substrate 114. The reagent reacts and/or becomes contaminated withmaterials from, or disposed on, the substrate 114 thereby becoming aneffluent (e.g., a first effluent). The effluent is disposed at the baseof the chamber 102 via the effluent line 106. The effluent line 106transfers heat from the effluent to a reagent in the fluid line 104 viathe heat exchanger 103. Similarly, a second effluent is exhausted fromthe chamber 452 via the effluent line 460 and is routed to the heat pump454. The second effluent is pressurized by the compressor 456, and theeffluent line 460 transfers heat from the pressurized second effluent tothe liquid reagent in the fluid line 104 via the heat pump heatexchanger 458. The reagent, having an elevated temperature from the heatrecovered from both the first and second effluents, requires lessenergy, if any, from the heater 120 prior to entering the processchamber 102. Thus, the recovered heat from the effluent may reduceenergy consumption by the processing system 400.

Alternative embodiments of the processing system 400 are possible. Forexample, the processing system 100 may optionally not include the heatexchanger 103 and may be solely pre-heated by the heat pump 454 of theprocessing system 150. In another alternative embodiment, the heater 120may be optionally excluded if the waste heat recovery system (e.g., theheat exchanger 103 and heat pump 454) are sufficient to pre-heat theincoming fluid to operating temperature. In some embodiments, the heatexchanger 103 may be located downstream of the heat pump 154.

Further alternatives of the processing system 400 are possible. Forexample, both the processing chambers 102, 452 may be wet benches, oralternatively, both may be configured for gaseous processes.

FIG. 5 illustrates a semiconductor processing system in accordance withsome embodiments of the present invention. For example, a semiconductorprocessing system 500 may be similar to the processing system 100 andthe processing system 450 except that the waste heat from bothprocessing systems pass through a common heat exchange apparatus 502.The semiconductor processing system 500, like processing system 400, maybe an exemplary portion of a fabrication line, and further such afabrication line may comprise a plurality of interconnected processsystems, and need not be limited to two systems as illustrated. Asillustrated in FIG. 5, the heat exchanger apparatus 502 may couple thesystems 100, 450 at the incoming fluid line 104 to facilitatepre-heating of a reagent prior to entering the process chamber 102.Similar to the concepts discussed above, the processing system 400 mayfacilitate the recovery of waste heat from both the processing systems100 and 450.

The heat exchange apparatus 502 is illustrated in detail in FIG. 5A. Theheat exchange apparatus 502 includes substantially all of the componentsfrom the heat exchanger 103 and the heat pump 454 as discussed for thesystem 400 above contained in a single enclosure. Specifically, the heatexchange apparatus 502 includes a first side comprising a portion of theincoming fluid reagent line 104 and a second side comprising a pluralityof heat exchange conduits (a first heat exchange conduit 558 and asecond heat exchange conduit 503 shown in FIG. 5). The plurality of heatexchange conduits may be viewed as separate heat exchangers each havinga coincident side for flowing the liquid reagent therethrough or as asingle heat exchanger with one side having a plurality of conduits forflowing waste heat fluids therethrough. A compressor is disposed in atleast one of the heat exchange conduits (compressor 556 shown coupledin-line with the first heat exchange conduit 558). As in the heat pumpsand heat exchangers discussed above, the first side of the heat exchangeapparatus 502 is robustly thermally coupled to all of the heat exchangeconduits disposed on the second side to facilitate efficientlytransferring as much heat as possible from the second side (wasteeffluent) to the first side (reagent).

In operation, the processing system 500 is substantially similar to theoperation of the processing system 400 as discussed above. However, andas noted above, waste heat from the effluents of each system 100, 450 isthermally coupled to an incoming reagent from the reagent source 108along a common portion of the incoming fluid line 104, where the commonportion of the incoming fluid line 104 forms the first side of the heatexchange apparatus 502. Accordingly, the waste heat from both systems100, 450 may be transferred to an incoming reagent simultaneously viaflowing effluent through respective heat exchanger conduits 503, 558.Alternatively, and depending on the duty cycles of each processingsystem, waste heat may be thermally transferred to an incoming reagentby alternating use of each heat exchange conduit 503, 558. Waste heatmay be thermally transferred to an incoming reagent by any suitablescheme as dictated by the duty cycles of each processing system 100,450. For example, if the duty cycle of the processing system 450 istwice that of the system 100, the heat exchange conduit 358 may beutilized to pre-heat an incoming reagent from the reagent source 108about twice as often as the heat exchange conduit 303. Further, any ofthe operation schemes discussed above for system 500 may be utilizedwith the system 400.

Alternative embodiments of the processing system 500 are possible. Forexample, both the processing chambers 102, 452 may be wet benches. Inembodiments, where the reagents supplied to each wet bench arechemically compatible, the exhaust lines 106, 460 may feed into a commonline (not shown). The common line, for example, may be utilized as thesecond side of a common heat exchanger, which replaces the individualsecond sides of the heat exchange conduits 503, 558. Further, the commonline may feed into a common exhaust system, which replaces theindividual exhaust systems 110, 462. Other alternatives embodiments arepossible. For example, both process chambers 102, 452 may be configuredfor gaseous processes. In embodiments, where gaseous reagents suppliedto each chamber are chemically compatible, the system 500 may beconfigured in a similar configuration as discussed above. In addition,in any of embodiments disclosed herein, where waste heat effluents fromdifferent sources are compatible, they may be aggregated prior toentering a common heat pump.

Embodiments of processing systems disclosed above have generally beendiscussed in the context of pre-heating a reagent prior to entering aprocess chamber. However, other apparatus may benefit from the presentinvention. For example, an ion exchanger such as one utilized for thegeneration of ultra-pure water (e.g., a liquid reagent) may benefit fromthe present invention. For example, apparatus as discussed above mayutilize waste heat from disposed effluents to pre-heat regenerationwater prior to flowing the regeneration water through an ion exchanger.For example, the regeneration water may be utilized to clean orregenerate the ion exchanger by removing ionic species collected in theexchanger. In some embodiments, the apparatus as discussed above may beused to recapture waste heat to drive a halopolymer (e.g., polymershaving halogen atoms incorporated therein, such as attached to theirbackbone) sub atmospheric acid distillation/purification system and orresin based concentrator to recover waste acids (such as HF, HCL, HNO₃,or other waste chemicals) and return them to be used in a process asreagents or cleaning solutions.

Methods for processing a substrate are described below. The inventivemethods may be utilized in the inventive processing systems discussedabove, however, other processing systems may benefit from the inventivemethods as well.

FIG. 6 illustrates a flow diagram of a method 600 for recovering heatfrom a disposed effluent in accordance with some embodiments of thepresent invention. The method 600 is described below with respect to thesystem 100 as illustrated in FIGS. 2, 4, and 5. The method 600 generallybegins at 602 by providing a process chamber having a heat exchangercoupled thereto, for example, the process chamber 102 and heat exchanger103 described above. As discussed above, the heat exchanger 103 has afirst side (e.g., in-line with incoming fluid line 104) for flowing aliquid reagent to the process chamber 102 and a second side (e.g.,in-line with effluent line 106) for flowing an effluent from the processchamber 102. The effluent line 106 may be thermally coupled to the fluidline 104 in any suitable configuration to maximize heat recovered fromthe effluent prior to disposal in the effluent system 110. In someembodiments, the effluent may flow into an intermediate reservoir 105and then flow from the intermediate reservoir 105 to the second side ofthe heat exchanger 103.

At 604, the liquid reagent may be pre-heated by the heat exchanger 103.For example, heat may be recovered from an effluent by diffusing intothe material of the effluent line 106. Such material may include anymaterial having high thermal conductivity, such as discussed above. Fromthe effluent line 106, heat may diffuse into the fluid line 104 andultimately to a reagent flowing along, or statically disposed, along theportion of the fluid line 104 thermally coupled to the effluent line106.

The liquid reagent may include, for example, water, ultra-pure water,de-ionized water, or the like, which may be utilized, for example, torinse the substrate 114 during a wet chemical etch or a wet chemicalcleaning process. Further, the liquid reagent may include any suitablechemical and/or chemical solution that requires heating prior to use inthe process chamber 102. For example, suitable chemicals and/or chemicalsolutions may include chemicals used in wet strip or wet etch process,such as hydrochloric acid (HCl), hydrofluoric acid (HF), ammoniumhydroxide (NH₄OH), hydrogen peroxide (H₂O₂), phosphoric acid (H₃PO₄), orsulfuric acid (H₂SO₄), or the like. Although the above example relatesto wet etch, wet strip, and wet chemical cleaning processes, any othersilicon processing that utilizes liquid reagents as disclosed herein.

The temperature of the liquid reagent prior to heat transfer may beabout room temperature, or between about 15 to about 180 degreesCelsius. Heat recovered from the effluent may pre-heat the liquidreagent to a temperature between about 30 to about 180 degrees Celsius.

At 606, the pre-heated liquid reagent to a desired temperature using,for example, the heater 120. For example, the heater 120 may heat thereagent to up to about 180 degrees Celsius, or between about 35 to about180 degrees Celsius. Upon heating the liquid reagent to a desiredtemperature, the method 600 generally ends by flowing the heated liquidreagent to the process chamber 102.

Alternatively, FIG. 7 illustrates a flow diagram of a method 700 forrecovering heat from a disposed effluent in accordance with someembodiments of the present invention. The method 700 is described withrespect to FIG. 2, but likewise may be utilized with systems 400 and 500illustrated in FIGS. 4-5. At 702, the liquid reagent is flowed throughthe first side of the heat exchanger 103 (e.g., in-line with theincoming fluid line 104) to pre-heat the liquid reagent. At 704, thepre-heated liquid reagent is heated to a desired temperature by theheater 120. At 706, the heated liquid reagent is flowed to the processchamber 102, where the heated liquid reagent may be utilized in a liquidprocess, such as a wet chemical etch of the substrate 114. The heatedliquid reagent becomes contaminated and/or reacts with the substrate 114to form an effluent. The effluent retains at least some heat from theheated liquid reagent. At 708, the effluent is flowed from the processchamber 102 through a second side of the heat exchanger 103 (e.g.,in-line with the effluent line 106) to pre-heat the liquid reagentflowing through the first side of the heat exchanger 103 (as depicted at710). In some embodiments, the process effluent may flow into anintermediate reservoir 105, and then flowed from the intermediatereservoir 105 to the second side of the heat exchanger 103.

FIG. 8 illustrates a flow diagram of a method 800 for recovering heatfrom a disposed effluent in accordance with some embodiments of thepresent invention. The method 800 may be utilized with any of FIGS. 3-5,and is generally described with respect to FIGS. 4-5. The method 800generally begins at 802 by providing a waste heat source, for example,the process chamber 452 having the heat pump 454 described above. Asdiscussed above, the heat pump 454 may include the compressor 456 andthe heat pump heat exchanger 458. The compressor 456 is utilized forpressurizing an effluent exhausted from the process chamber 452 or aheat transfer fluid flowing in an inner conduit of the heat pump 454.The pressurization of the exhausted effluent or heat transfer fluidraises the temperature of the effluent or the heat transfer fluid inaccordance with ideal gas law behavior. The heat pump heat exchanger 458has a first side (e.g., in-line with incoming fluid line 104) forflowing a liquid reagent to a second process chamber (e.g., processchamber 102) and a second side (e.g., in-line with effluent line 460)for flowing the pressurized effluent from the process chamber 452. Theeffluent line 460 may be thermally coupled to the fluid line 104 in anysuitable configuration to maximize heat recovered from the effluentprior to disposal in the effluent system 462. Alternatively, the heatpump 454 may be configured with an internal heat transfer loop forcycling a heat transfer fluid between a first portion of the heat pumpfor transferring heat to the heat transfer fluid from the waste heatsource and a second portion of the heat pump for transferring heat fromthe heat transfer fluid to a reagent flowing in the fluid line.

At 804, a first effluent is exhausted from the waste heat source (e.g.,process chamber 452). The first effluent may be in a gaseous form, andmay be for example, a process gas or gaseous byproduct of asemiconductor process, such as an etch process, deposition process, orany suitable process resulting in an effluent from which waste heat canbe recovered. Alternatively, or in combination, waste heat from othersources of the processing system may be captured, such as fromcompressed air systems, air separation compressors, pumps, electricaland/or mechanical equipment, abatement devices, or the like.Alternatively, the waste heat might be captured by a liquid coolant.

Optionally, at 806, the first effluent may be pressurized. For example,the compressor 456 may compress the first effluent, thus increasing thetemperature of the first effluent. The increase in temperature bypressurization may facilitate improved heat transfer between the firsteffluent and a reagent to be heated. Alternatively, the first effluentmay be routed through the heat pump to transfer heat to the heattransfer fluid, which is then pressurized and pumped through the heatpump to the portion used for heating the reagent in the fluid line.

At 808, a reagent may be pre-heated by transferring waste heat from thefirst effluent to the reagent. For example, the reagent may bestatically disposed in, or flowing through, a portion of the incomingfluid line 104 (e.g., the first side of the heat pump heat exchanger458, or coupled to a portion of the heat pump 454) coupled to a processchamber (e.g., process chamber 102). The reagent may be pre-heated bytransferring waste heat from the first effluent flowing through, orstatically disposed in, a portion of the exhaust line 460 (e.g., thesecond side of the heat pump heat exchanger 458, or coupled to a portionof the heat pump 454).

The reagent may include, for example, water, ultra-pure water,de-ionized water, or the like, which may be utilized, for example, torinse the substrate 114 during a wet chemical etch or a wet chemicalcleaning process. Further, the liquid reagent may include any suitablechemical and/or chemical solution that requires heating prior to use inthe process chamber 102. For example, suitable chemicals and/or chemicalsolutions may include acids, bases and/or solvents used in wet strip orwet etch process or wet cleaning processes, such as hydrochloric acid(HCl), hydrofluoric acid (HF), ammonium hydroxide (NH₄OH), hydrogenperoxide (H₂O₂), phosphoric acid (H₃PO₄), or sulfuric acid (H₂SO₄), orthe like. Although the above example relates to wet etch, wet strip, andwet chemical cleaning processes, the present invention is applicable toother substrate processing that utilizes liquid or gaseous reagents asdisclosed herein.

In some embodiments, for illustration, the temperature of the reagentprior to heat transfer may be about room temperature, or between about15 to about 30 degrees Celsius. Waste heat recovered from the effluentmay pre-heat the reagent to a temperature between about 30 to about 180degrees Celsius.

In some embodiments, the heated reagent may be then flowed to theprocess chamber for use therein, as shown at 814. Upon providing theheated reagent to the process chamber 102, or to some other destination,the method 800 generally ends. However, additional embodiments of themethod 800 are possible. For example, should waste heat from thepressurized first effluent not sufficiently pre-heat the reagent toprocessing temperatures, the heater 120 may be utilized to furtherpre-heat the reagent to a desired processing temperature.

Further, waste heat may be recovered from others sources and utilized topre-heat the reagent in combination with the waste heat recovered fromthe first effluent. For example, after processing in the process chamber102, the reagent may be converted to a second effluent that is exhaustedfrom the process chamber 102. For example, the second effluent mayinclude the reagent, as well as byproducts materials, such as materialsfrom a substrate being processed. The second effluent, partially formedfrom the heated reagent, may have waste heat which can be recovered.

In some embodiments, as shown at 810 in phantom, the second effluent maybe exhausted from the process chamber 102. The second effluent may havewaste heat that can be recovered to pre-heat the reagent to be used inthe process chamber 102.

As such, at 812, the reagent may be further pre-heated for use in theprocess chamber 102 by transferring waste heat from the second effluentto the reagent. In some embodiments, the reagent may be pre-heated bytransferring waste heat from the second effluent through a heat pump. Insome embodiments, the reagent may be pre-heated by transferring wasteheat from the second effluent through a heat exchanger. In someembodiments, the reagent may be statically disposed, or flowing through,a portion of the incoming fluid line 104 (e.g., the first side of heatexchanger 103) coupled to a process chamber (e.g., process chamber 102).The reagent may be pre-heated by transferring waste heat from the secondeffluent flowing through, or statically disposed in, a portion of theexhaust line 106 (e.g., the second side of the heat exchanger 103).

The heat exchanger 103 may be utilized for pre-heating the reagent inaddition to, in alternation with, or in place of the heat pump 458. Asdiscussed above, the heat exchanger 103 may be located downstream of(not shown), upstream of (FIG. 4), or overlapping with (similar to FIG.5) the heat pump 458.

Waste heat from the second effluent need not be recycled to heat areagent entered the same process chamber (e.g., process chamber 102)from which the second effluent was generated. For example, waste heatfrom the second effluent may be utilized to pre-heat a reagent for usein a different process chamber (similar to FIGS. 4-5).

Thus, methods and apparatus for recovering heat from disposed effluentshave been disclosed herein. The inventive methods and apparatusadvantageously facilitate reduced energy consumption of a semiconductoror other processing system by utilizing heat from disposed effluents topre-heat reagents entering the processing system. The reduction of heatin the disposed effluents is further advantageous for subsequentprocessing of the disposed effluents, such as abatement.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof.

1. A substrate processing system, comprising: a process chamberconfigured for liquid processes; a first heat exchanger having first andsecond sides configured to transfer heat therebetween, wherein the firstside is configured to flow a liquid reagent therethrough and into theprocess chamber, and wherein the second side is configured to flow aneffluent from the process chamber therethrough; and a heater disposed inline with the first side of the first heat exchanger to heat the liquidreagent prior to entering the process chamber.
 2. The system of claim 1,further comprising: an intermediate reservoir disposed between theprocess chamber and the first heat exchanger to collect effluent fromthe process chamber and to pump the effluent through the first heatexchanger.
 3. The system of claim 1, further comprising: a first wasteheat source for providing a first waste fluid having waste heat storedtherein; a heat pump coupled between the first waste heat source and anincoming fluid line that flows the liquid reagent into the processchamber, the heat pump configured to transfer heat from the first wasteheat source to the liquid reagent in the incoming fluid line.
 4. Thesystem of claim 3, wherein the heat pump is disposed between the heaterand the first heat exchanger.
 5. The system of claim 3, wherein thewaste heat source includes one or more of a process chamber configuredfor liquid or gaseous processes, a compressed air system, an airseparation compressor, an air compressor, or an abatement device.
 6. Thesystem of claim 3, further comprising: a second waste heat source, toprovide a second waste heat fluid having waste heat stored therein tothe heat pump to transfer the waste heat stored therein to the liquidreagent in the incoming fluid line.
 7. The system of claim 1, furthercomprising: a first waste heat source for providing a first waste fluidhaving waste heat stored therein; a heat pump having a compressor and asecond heat exchanger, wherein the compressor is coupled in line withthe first waste heat source and a first side of the second heatexchanger, and wherein the second side of the second heat exchanger isconfigured to flow the liquid reagent therethrough and into the processchamber.
 8. The system of claim 7, wherein the first side of the firstheat exchanger and the second side of the second heat exchanger arecoincident.
 9. A substrate processing system, comprising: a waste heatsource for providing a first waste fluid having waste heat storedtherein; a first process chamber having a reagent source coupled theretoand configured to provide a reagent to an inner volume of the firstprocess chamber; and a heat pump coupled between the waste heat sourceand an incoming reagent line that flows the reagent into the innervolume of the process chamber, the heat pump configured to transfer heatfrom the waste heat source to the reagent in the incoming reagent line.10. The system of claim 9, further comprising: a heater disposed in linewith the heat pump to further heat the reagent prior to entering thefirst process chamber.
 11. The system of claim 9, wherein the waste heatsource comprises one or more of a process chamber configured for gaseousprocesses, a compressed air system, an air separation compressor, anabatement device, electrical equipment or mechanical equipment.
 12. Thesystem of claim 9, wherein the first process chamber is configured forliquid processes, and wherein the waste heat source comprises a secondprocess chamber configured for gaseous processes and providing the firstwaste fluid as gaseous exhaust from the second process chamber.
 13. Thesystem of claim 12, wherein the heat pump further comprises: acompressor and a first heat exchanger, wherein the compressor is coupledin line with the waste heat source and a first side of the first heatexchanger to pressurize the first waste fluid and prior to the firstwaste fluid flowing through the first side of the heat exchanger, andwherein a second side of the first heat exchanger is configured to flowthe reagent therethrough.
 14. The system of claim 13, furthercomprising: a second heat exchanger having first and second sidesconfigured to transfer heat therebetween, wherein the first side of thesecond heat exchanger is configured to flow the reagent therethrough andinto the first process chamber, and wherein the second side of thesecond heat exchanger is configured to flow a second waste fluidexhausted from the first process chamber therethrough.
 15. The system ofclaim 14, wherein the second side of the first heat exchanger and thefirst side of the second heat exchanger are coincident.
 16. The systemof claim 14, further comprising: a heater disposed in line with thesecond side of the first heat exchanger and the first side of the secondheat exchanger to heat the reagent prior to entering the first processchamber.
 17. The system of claim 16, wherein the heat pump is disposedbetween the heater and the second heat exchanger.
 18. A method forprocessing a substrate, comprising: providing a process chamberconfigured for liquid processes coupled to a heat exchanger having afirst side for flowing a liquid reagent into the processing system and asecond side for flowing an effluent from the process chamber;pre-heating the liquid reagent by transferring heat from the effluentflowing through the second side of the heat exchanger to the reagentflowing through the first side of the heat exchanger; and heating thepre-heated liquid reagent to a desired temperature using a heaterdisposed between the heat exchanger and the process chamber.
 19. Themethod of claim 18, wherein pre-heating the liquid reagent furthercomprises: flowing the effluent into an intermediate reservoir; andflowing the effluent from the intermediate reservoir to the second sideof the heat exchanger.
 20. A method for processing a substrate,comprising: flowing a liquid reagent through a first side of a heatexchanger to preheat the liquid reagent; heating the pre-heated liquidreagent to a desired temperature using a heater; flowing the heatedliquid reagent to a process chamber configured for liquid processes; andflowing a process effluent from the chamber through a second side of theheat exchanger to pre-heat the liquid reagent flowing through the firstside of the heat exchanger.
 21. The method of claim 20, furthercomprising: flowing the process effluent into an intermediate reservoir;and flowing the process effluent from the intermediate reservoir to thesecond side of the heat exchanger.
 22. A method for processing asubstrate, comprising: flowing a reagent through a heat pump coupled toa waste heat source to heat the reagent by transferring heat from thewaste heat source to the reagent; and flowing the heated reagent to aprocess chamber to process the substrate.
 23. The method of claim 22,wherein the waste heat source comprises one or more of a liquid orgaseous effluent exhausted from a second process chamber, a compressedair system, an air separation compressor, liquid coolant from or agaseous exhaust from an abatement device, liquid coolant from or hot airfrom electrical and/or mechanical equipment.
 24. The method of claim 22,further comprising: further heating the heated reagent to a desiredtemperature using a heater disposed between the heat pump and theprocess chamber.
 25. The method of claim 22, further comprising flowingthe reagent through a first side of a heat exchanger disposed in linewith the heat pump; and flowing an effluent exhausted from the firstprocess chamber through a second side of the heat exchanger to heat thereagent flowing through the first side of the heat exchanger.